2 * Copyright (c) 2015 Brocade Communications Systems, Inc. and others. All rights reserved.
4 * This program and the accompanying materials are made available under the
5 * terms of the Eclipse Public License v1.0 which accompanies this distribution,
6 * and is available at http://www.eclipse.org/legal/epl-v10.html
8 package org.opendaylight.controller.cluster.raft.behaviors;
10 import static org.junit.Assert.assertEquals;
11 import akka.actor.ActorRef;
12 import com.google.common.collect.ImmutableMap;
13 import org.junit.Test;
14 import org.opendaylight.controller.cluster.raft.DefaultConfigParamsImpl;
15 import org.opendaylight.controller.cluster.raft.MockRaftActorContext.MockPayload;
16 import org.opendaylight.controller.cluster.raft.MockRaftActorContext.MockReplicatedLogEntry;
17 import org.opendaylight.controller.cluster.raft.MockRaftActorContext.SimpleReplicatedLog;
18 import org.opendaylight.controller.cluster.raft.RaftState;
19 import org.opendaylight.controller.cluster.raft.base.messages.ElectionTimeout;
20 import org.opendaylight.controller.cluster.raft.messages.RequestVote;
21 import org.opendaylight.controller.cluster.raft.messages.RequestVoteReply;
24 * A leader election scenario test that partitions a candidate when trying to join a cluster on startup.
26 * @author Thomas Pantelis
28 public class PartitionedCandidateOnStartupElectionScenarioTest extends AbstractLeaderElectionScenarioTest {
30 private final int numCandidateElections = 5;
31 private long candidateElectionTerm;
34 public void runTest() throws Exception {
35 testLog.info("PartitionedCandidateOnStartupElectionScenarioTest starting");
37 setupInitialMember1AndMember2Behaviors();
39 setupPartitionedCandidateMember3AndSendElectionTimeouts();
41 resolvePartitionAndSendElectionTimeoutsToCandidateMember3();
43 sendElectionTimeoutToFollowerMember1();
45 testLog.info("PartitionedCandidateOnStartupElectionScenarioTest ending");
48 private void sendElectionTimeoutToFollowerMember1() throws Exception {
49 testLog.info("sendElectionTimeoutToFollowerMember1 starting");
51 // At this point we have no leader. Candidate member 3 would continue to start new elections
52 // but wouldn't be granted a vote. One of the 2 followers would eventually time out from
53 // not having received a heartbeat from a leader and switch to candidate and start a new
54 // election. We'll simulate that here by sending an ElectionTimeout to member 1.
57 member1Actor.expectMessageClass(RequestVoteReply.class, 1);
59 member2Actor.expectMessageClass(RequestVote.class, 1);
61 member3Actor.expectMessageClass(RequestVote.class, 1);
62 member3Actor.expectBehaviorStateChange();
64 member1ActorRef.tell(new ElectionTimeout(), ActorRef.noSender());
66 member2Actor.waitForExpectedMessages(RequestVote.class);
67 member3Actor.waitForExpectedMessages(RequestVote.class);
69 // The RequestVoteReply should come from Follower member 2 and the vote should be granted
70 // since member 2's last term and index matches member 1's.
72 member1Actor.waitForExpectedMessages(RequestVoteReply.class);
74 RequestVoteReply requestVoteReply = member1Actor.getCapturedMessage(RequestVoteReply.class);
75 assertEquals("getTerm", member1Context.getTermInformation().getCurrentTerm(), requestVoteReply.getTerm());
76 assertEquals("isVoteGranted", true, requestVoteReply.isVoteGranted());
78 // Candidate member 3 should change to follower as its term should be less than the
79 // RequestVote term (member 1 started a new term higher than the other member's terms).
81 member3Actor.waitForBehaviorStateChange();
83 verifyBehaviorState("member 1", member1Actor, RaftState.Leader);
84 verifyBehaviorState("member 2", member2Actor, RaftState.Follower);
85 verifyBehaviorState("member 3", member3Actor, RaftState.Follower);
87 // newTerm should be 10.
89 long newTerm = candidateElectionTerm + 1;
90 assertEquals("member 1 election term", newTerm, member1Context.getTermInformation().getCurrentTerm());
91 assertEquals("member 2 election term", newTerm, member2Context.getTermInformation().getCurrentTerm());
92 assertEquals("member 3 election term", newTerm, member3Context.getTermInformation().getCurrentTerm());
94 testLog.info("sendElectionTimeoutToFollowerMember1 ending");
97 private void resolvePartitionAndSendElectionTimeoutsToCandidateMember3() throws Exception {
98 testLog.info("resolvePartitionAndSendElectionTimeoutsToCandidateMember3 starting");
100 // Now send a couple more ElectionTimeouts to Candidate member 3 with the partition resolved.
102 // On the first RequestVote, Leader member 1 should switch to Follower as its term (s) is less than
103 // the RequestVote's term (8) from member 3. No RequestVoteReply should be sent by member 1.
104 // Follower member 2 should update its term since it less than the RequestVote's term and
105 // should return a RequestVoteReply but should not grant the vote as its last term and index
106 // is greater than the RequestVote's lastLogTerm and lastLogIndex, ie member 2's log is later
107 // or more up to date than member 3's.
109 // On the second RequestVote, both member 1 and 2 are followers so they should update their
110 // term and return a RequestVoteReply but should not grant the vote.
112 candidateElectionTerm += 2;
113 for(int i = 0; i < 2; i++) {
114 member1Actor.clear();
115 member1Actor.expectMessageClass(RequestVote.class, 1);
116 member2Actor.clear();
117 member2Actor.expectMessageClass(RequestVote.class, 1);
118 member3Actor.clear();
119 member3Actor.expectMessageClass(RequestVoteReply.class, 1);
121 member3ActorRef.tell(new ElectionTimeout(), ActorRef.noSender());
123 member1Actor.waitForExpectedMessages(RequestVote.class);
124 member2Actor.waitForExpectedMessages(RequestVote.class);
126 member3Actor.waitForExpectedMessages(RequestVoteReply.class);
128 RequestVoteReply requestVoteReply = member3Actor.getCapturedMessage(RequestVoteReply.class);
129 assertEquals("getTerm", member3Context.getTermInformation().getCurrentTerm(), requestVoteReply.getTerm());
130 assertEquals("isVoteGranted", false, requestVoteReply.isVoteGranted());
133 verifyBehaviorState("member 1", member1Actor, RaftState.Follower);
134 verifyBehaviorState("member 2", member2Actor, RaftState.Follower);
135 verifyBehaviorState("member 3", member3Actor, RaftState.Candidate);
137 // Even though member 3 didn't get voted for, member 1 and 2 should have updated their term
140 assertEquals("member 1 election term", candidateElectionTerm,
141 member1Context.getTermInformation().getCurrentTerm());
142 assertEquals("member 2 election term", candidateElectionTerm,
143 member2Context.getTermInformation().getCurrentTerm());
144 assertEquals("member 3 election term", candidateElectionTerm,
145 member3Context.getTermInformation().getCurrentTerm());
147 testLog.info("resolvePartitionAndSendElectionTimeoutsToCandidateMember3 ending");
150 private void setupPartitionedCandidateMember3AndSendElectionTimeouts() {
151 testLog.info("setupPartitionedCandidateMember3AndSendElectionTimeouts starting");
153 // Create member 3's behavior initially as a Candidate.
155 member3Context = newRaftActorContext("member3", member3ActorRef,
156 ImmutableMap.<String,String>builder().
157 put("member1", member1ActorRef.path().toString()).
158 put("member2", member2ActorRef.path().toString()).build());
160 DefaultConfigParamsImpl member3ConfigParams = newConfigParams();
161 member3Context.setConfigParams(member3ConfigParams);
163 // Initialize the ReplicatedLog and election term info for Candidate member 3. The current term
164 // will be 2 and the last term will be 1 so it is behind the leader's log.
166 SimpleReplicatedLog candidateReplicatedLog = new SimpleReplicatedLog();
167 candidateReplicatedLog.append(new MockReplicatedLogEntry(1, 1, new MockPayload("")));
168 candidateReplicatedLog.append(new MockReplicatedLogEntry(2, 1, new MockPayload("")));
170 member3Context.setReplicatedLog(candidateReplicatedLog);
171 member3Context.getTermInformation().update(2, member1Context.getId());
173 // The member 3 Candidate will start a new term and send RequestVotes. However it will be
174 // partitioned from the cluster by having member 1 and 2 drop its RequestVote messages.
176 candidateElectionTerm = member3Context.getTermInformation().getCurrentTerm() + numCandidateElections;
178 member1Actor.dropMessagesToBehavior(RequestVote.class, numCandidateElections);
180 member2Actor.dropMessagesToBehavior(RequestVote.class, numCandidateElections);
182 Candidate member3Behavior = new Candidate(member3Context);
183 member3Actor.behavior = member3Behavior;
185 // Send several additional ElectionTimeouts to Candidate member 3. Each ElectionTimeout will
186 // start a new term so Candidate member 3's current term will be greater than the leader's
189 for(int i = 0; i < numCandidateElections - 1; i++) {
190 member3ActorRef.tell(new ElectionTimeout(), ActorRef.noSender());
193 member1Actor.waitForExpectedMessages(RequestVote.class);
194 member2Actor.waitForExpectedMessages(RequestVote.class);
196 verifyBehaviorState("member 1", member1Actor, RaftState.Leader);
197 verifyBehaviorState("member 2", member2Actor, RaftState.Follower);
198 verifyBehaviorState("member 3", member3Actor, RaftState.Candidate);
200 assertEquals("member 1 election term", 3, member1Context.getTermInformation().getCurrentTerm());
201 assertEquals("member 2 election term", 3, member2Context.getTermInformation().getCurrentTerm());
202 assertEquals("member 3 election term", candidateElectionTerm,
203 member3Context.getTermInformation().getCurrentTerm());
205 testLog.info("setupPartitionedCandidateMember3AndSendElectionTimeouts ending");
208 private void setupInitialMember1AndMember2Behaviors() throws Exception {
209 testLog.info("setupInitialMember1AndMember2Behaviors starting");
211 // Create member 2's behavior as Follower.
213 member2Context = newRaftActorContext("member2", member2ActorRef,
214 ImmutableMap.<String,String>builder().
215 put("member1", member1ActorRef.path().toString()).
216 put("member3", member3ActorRef.path().toString()).build());
218 DefaultConfigParamsImpl member2ConfigParams = newConfigParams();
219 member2Context.setConfigParams(member2ConfigParams);
221 Follower member2Behavior = new Follower(member2Context);
222 member2Actor.behavior = member2Behavior;
224 // Create member 1's behavior as Leader.
226 member1Context = newRaftActorContext("member1", member1ActorRef,
227 ImmutableMap.<String,String>builder().
228 put("member2", member2ActorRef.path().toString()).
229 put("member3", member3ActorRef.path().toString()).build());
231 DefaultConfigParamsImpl member1ConfigParams = newConfigParams();
232 member1Context.setConfigParams(member1ConfigParams);
234 initializeLeaderBehavior(member1Actor, member1Context, 1);
236 member2Actor.clear();
237 member3Actor.clear();
239 // Initialize the ReplicatedLog and election term info for member 1 and 2. The current term
240 // will be 3 and the last term will be 2.
242 SimpleReplicatedLog replicatedLog = new SimpleReplicatedLog();
243 replicatedLog.append(new MockReplicatedLogEntry(2, 1, new MockPayload("")));
244 replicatedLog.append(new MockReplicatedLogEntry(3, 1, new MockPayload("")));
246 member1Context.setReplicatedLog(replicatedLog);
247 member1Context.getTermInformation().update(3, "");
249 member2Context.setReplicatedLog(replicatedLog);
250 member2Context.getTermInformation().update(3, member1Context.getId());
252 testLog.info("setupInitialMember1AndMember2Behaviors ending");